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diff --git a/methods/connect.cc b/methods/connect.cc
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+++ b/methods/connect.cc
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+// -*- mode: cpp; mode: fold -*-
+// Description /*{{{*/
+/* ######################################################################
+
+ Connect - Replacement connect call
+
+ This was originally authored by Jason Gunthorpe <jgg@debian.org>
+ and is placed in the Public Domain, do with it what you will.
+
+ ##################################################################### */
+ /*}}}*/
+// Include Files /*{{{*/
+#include <config.h>
+
+#include <apt-pkg/acquire-method.h>
+#include <apt-pkg/configuration.h>
+#include <apt-pkg/error.h>
+#include <apt-pkg/fileutl.h>
+#include <apt-pkg/srvrec.h>
+#include <apt-pkg/strutl.h>
+
+#include <gnutls/gnutls.h>
+#include <gnutls/x509.h>
+
+#include <cerrno>
+#include <cstdio>
+#include <cstring>
+#include <list>
+#include <set>
+#include <sstream>
+#include <string>
+#include <unistd.h>
+
+// Internet stuff
+#include <netdb.h>
+#include <arpa/inet.h>
+#include <netinet/in.h>
+#include <sys/select.h>
+#include <sys/socket.h>
+
+#include "aptmethod.h"
+#include "connect.h"
+#include "rfc2553emu.h"
+#include <apti18n.h>
+ /*}}}*/
+
+static std::string LastHost;
+static std::string LastService;
+static struct addrinfo *LastHostAddr = 0;
+static struct addrinfo *LastUsed = 0;
+
+static std::vector<SrvRec> SrvRecords;
+
+// Set of IP/hostnames that we timed out before or couldn't resolve
+static std::set<std::string> bad_addr;
+
+// RotateDNS - Select a new server from a DNS rotation /*{{{*/
+// ---------------------------------------------------------------------
+/* This is called during certain errors in order to recover by selecting a
+ new server */
+void RotateDNS()
+{
+ if (LastUsed != 0 && LastUsed->ai_next != 0)
+ LastUsed = LastUsed->ai_next;
+ else
+ LastUsed = LastHostAddr;
+}
+ /*}}}*/
+static bool ConnectionAllowed(char const * const Service, std::string const &Host)/*{{{*/
+{
+ if (unlikely(Host.empty())) // the only legal empty host (RFC2782 '.' target) is detected by caller
+ return false;
+ if (APT::String::Endswith(Host, ".onion") && _config->FindB("Acquire::BlockDotOnion", true))
+ {
+ // TRANSLATOR: %s is e.g. Tor's ".onion" which would likely fail or leak info (RFC7686)
+ _error->Error(_("Direct connection to %s domains is blocked by default."), ".onion");
+ if (strcmp(Service, "http") == 0)
+ _error->Error(_("If you meant to use Tor remember to use %s instead of %s."), "tor+http", "http");
+ return false;
+ }
+ return true;
+}
+ /*}}}*/
+
+// File Descriptor based Fd /*{{{*/
+struct FdFd : public MethodFd
+{
+ int fd = -1;
+ int Fd() APT_OVERRIDE { return fd; }
+ ssize_t Read(void *buf, size_t count) APT_OVERRIDE { return ::read(fd, buf, count); }
+ ssize_t Write(void *buf, size_t count) APT_OVERRIDE { return ::write(fd, buf, count); }
+ int Close() APT_OVERRIDE
+ {
+ int result = 0;
+ if (fd != -1)
+ result = ::close(fd);
+ fd = -1;
+ return result;
+ }
+};
+
+bool MethodFd::HasPending()
+{
+ return false;
+}
+std::unique_ptr<MethodFd> MethodFd::FromFd(int iFd)
+{
+ FdFd *fd = new FdFd();
+ fd->fd = iFd;
+ return std::unique_ptr<MethodFd>(fd);
+}
+ /*}}}*/
+// DoConnect - Attempt a connect operation /*{{{*/
+// ---------------------------------------------------------------------
+/* This helper function attempts a connection to a single address. */
+struct Connection
+{
+ struct addrinfo *Addr;
+ std::string Host;
+ aptMethod *Owner;
+ std::unique_ptr<FdFd> Fd;
+ char Name[NI_MAXHOST];
+ char Service[NI_MAXSERV];
+
+ Connection(struct addrinfo *Addr, std::string const &Host, aptMethod *Owner) : Addr(Addr), Host(Host), Owner(Owner), Fd(new FdFd()), Name{0}, Service{0}
+ {
+ }
+
+ // Allow moving values, but not connections.
+ Connection(Connection &&Conn) = default;
+ Connection(const Connection &Conn) = delete;
+ Connection &operator=(const Connection &) = delete;
+ Connection &operator=(Connection &&Conn) = default;
+
+ ~Connection()
+ {
+ if (Fd != nullptr)
+ {
+ Fd->Close();
+ }
+ }
+
+ std::unique_ptr<MethodFd> Take()
+ {
+ /* Store the IP we are using.. If something goes
+ wrong this will get tacked onto the end of the error message */
+ std::stringstream ss;
+ ioprintf(ss, _("[IP: %s %s]"), Name, Service);
+ Owner->SetIP(ss.str());
+ Owner->Status(_("Connected to %s (%s)"), Host.c_str(), Name);
+ _error->Discard();
+ Owner->SetFailReason("");
+ LastUsed = Addr;
+ return std::move(Fd);
+ }
+
+ ResultState DoConnect();
+
+ ResultState CheckError();
+};
+
+ResultState Connection::DoConnect()
+{
+ getnameinfo(Addr->ai_addr,Addr->ai_addrlen,
+ Name,sizeof(Name),Service,sizeof(Service),
+ NI_NUMERICHOST|NI_NUMERICSERV);
+ Owner->Status(_("Connecting to %s (%s)"),Host.c_str(),Name);
+
+ // if that addr did timeout before, we do not try it again
+ if(bad_addr.find(std::string(Name)) != bad_addr.end())
+ return ResultState::TRANSIENT_ERROR;
+
+ // Get a socket
+ if ((static_cast<FdFd *>(Fd.get())->fd = socket(Addr->ai_family, Addr->ai_socktype,
+ Addr->ai_protocol)) < 0)
+ {
+ _error->Errno("socket", _("Could not create a socket for %s (f=%u t=%u p=%u)"),
+ Name, Addr->ai_family, Addr->ai_socktype, Addr->ai_protocol);
+ return ResultState::FATAL_ERROR;
+ }
+
+ SetNonBlock(Fd->Fd(), true);
+ if (connect(Fd->Fd(), Addr->ai_addr, Addr->ai_addrlen) < 0 &&
+ errno != EINPROGRESS)
+ {
+ _error->Errno("connect", _("Cannot initiate the connection "
+ "to %s:%s (%s)."),
+ Host.c_str(), Service, Name);
+ return ResultState::TRANSIENT_ERROR;
+ }
+
+ return ResultState::SUCCESSFUL;
+}
+
+ResultState Connection::CheckError()
+{
+ // Check the socket for an error condition
+ unsigned int Err;
+ unsigned int Len = sizeof(Err);
+ if (getsockopt(Fd->Fd(), SOL_SOCKET, SO_ERROR, &Err, &Len) != 0)
+ {
+ _error->Errno("getsockopt", _("Failed"));
+ return ResultState::FATAL_ERROR;
+ }
+
+ if (Err != 0)
+ {
+ errno = Err;
+ if(errno == ECONNREFUSED)
+ Owner->SetFailReason("ConnectionRefused");
+ else if (errno == ETIMEDOUT)
+ Owner->SetFailReason("ConnectionTimedOut");
+ bad_addr.insert(bad_addr.begin(), std::string(Name));
+ _error->Errno("connect", _("Could not connect to %s:%s (%s)."), Host.c_str(),
+ Service, Name);
+ return ResultState::TRANSIENT_ERROR;
+ }
+
+ Owner->SetFailReason("");
+
+ return ResultState::SUCCESSFUL;
+}
+ /*}}}*/
+// Order the given host names returned by getaddrinfo() /*{{{*/
+static std::vector<struct addrinfo *> OrderAddresses(struct addrinfo *CurHost)
+{
+ std::vector<struct addrinfo *> preferredAddrs;
+ std::vector<struct addrinfo *> otherAddrs;
+ std::vector<struct addrinfo *> allAddrs;
+
+ // Partition addresses into preferred and other address families
+ while (CurHost != 0)
+ {
+ if (preferredAddrs.empty() || CurHost->ai_family == preferredAddrs[0]->ai_family)
+ preferredAddrs.push_back(CurHost);
+ else
+ otherAddrs.push_back(CurHost);
+
+ // Ignore UNIX domain sockets
+ do
+ {
+ CurHost = CurHost->ai_next;
+ } while (CurHost != 0 && CurHost->ai_family == AF_UNIX);
+
+ /* If we reached the end of the search list then wrap around to the
+ start */
+ if (CurHost == 0 && LastUsed != 0)
+ CurHost = LastHostAddr;
+
+ // Reached the end of the search cycle
+ if (CurHost == LastUsed)
+ break;
+ }
+
+ // Build a new address vector alternating between preferred and other
+ for (auto prefIter = preferredAddrs.cbegin(), otherIter = otherAddrs.cbegin();
+ prefIter != preferredAddrs.end() || otherIter != otherAddrs.end();)
+ {
+ if (prefIter != preferredAddrs.end())
+ allAddrs.push_back(*prefIter++);
+ if (otherIter != otherAddrs.end())
+ allAddrs.push_back(*otherIter++);
+ }
+
+ return allAddrs;
+}
+ /*}}}*/
+// Check for errors and report them /*{{{*/
+static ResultState WaitAndCheckErrors(std::list<Connection> &Conns, std::unique_ptr<MethodFd> &Fd, long TimeoutMsec, bool ReportTimeout)
+{
+ // The last error detected
+ ResultState Result = ResultState::TRANSIENT_ERROR;
+
+ struct timeval tv = {
+ // Split our millisecond timeout into seconds and microseconds
+ .tv_sec = TimeoutMsec / 1000,
+ .tv_usec = (TimeoutMsec % 1000) * 1000,
+ };
+
+ // We will return once we have no more connections, a time out, or
+ // a success.
+ while (!Conns.empty())
+ {
+ fd_set Set;
+ int nfds = -1;
+
+ FD_ZERO(&Set);
+
+ for (auto &Conn : Conns)
+ {
+ int fd = Conn.Fd->Fd();
+ FD_SET(fd, &Set);
+ nfds = std::max(nfds, fd);
+ }
+
+ {
+ int Res;
+ do
+ {
+ Res = select(nfds + 1, 0, &Set, 0, (TimeoutMsec != 0 ? &tv : 0));
+ } while (Res < 0 && errno == EINTR);
+
+ if (Res == 0)
+ {
+ if (ReportTimeout)
+ {
+ for (auto &Conn : Conns)
+ {
+ Conn.Owner->SetFailReason("Timeout");
+ bad_addr.insert(bad_addr.begin(), Conn.Name);
+ _error->Error(_("Could not connect to %s:%s (%s), "
+ "connection timed out"),
+ Conn.Host.c_str(), Conn.Service, Conn.Name);
+ }
+ }
+ return ResultState::TRANSIENT_ERROR;
+ }
+ }
+
+ // iterate over connections, remove failed ones, and return if
+ // there was a successful one.
+ for (auto ConnI = Conns.begin(); ConnI != Conns.end();)
+ {
+ if (!FD_ISSET(ConnI->Fd->Fd(), &Set))
+ {
+ ConnI++;
+ continue;
+ }
+
+ Result = ConnI->CheckError();
+ if (Result == ResultState::SUCCESSFUL)
+ {
+ Fd = ConnI->Take();
+ return Result;
+ }
+
+ // Connection failed. Erase it and continue to next position
+ ConnI = Conns.erase(ConnI);
+ }
+ }
+
+ return Result;
+}
+ /*}}}*/
+// Connect to a given Hostname /*{{{*/
+static ResultState ConnectToHostname(std::string const &Host, int const Port,
+ const char *const Service, int DefPort, std::unique_ptr<MethodFd> &Fd,
+ unsigned long const TimeOut, aptMethod *const Owner)
+{
+ if (ConnectionAllowed(Service, Host) == false)
+ return ResultState::FATAL_ERROR;
+
+ // Used by getaddrinfo(); prefer port if given, else fallback to service
+ std::string ServiceNameOrPort = Port != 0 ? std::to_string(Port) : Service;
+
+ /* We used a cached address record.. Yes this is against the spec but
+ the way we have setup our rotating dns suggests that this is more
+ sensible */
+ if (LastHost != Host || LastService != ServiceNameOrPort)
+ {
+ Owner->Status(_("Connecting to %s"),Host.c_str());
+
+ // Free the old address structure
+ if (LastHostAddr != 0)
+ {
+ freeaddrinfo(LastHostAddr);
+ LastHostAddr = 0;
+ LastUsed = 0;
+ }
+
+ // We only understand SOCK_STREAM sockets.
+ struct addrinfo Hints;
+ memset(&Hints,0,sizeof(Hints));
+ Hints.ai_socktype = SOCK_STREAM;
+ Hints.ai_flags = 0;
+#ifdef AI_IDN
+ if (_config->FindB("Acquire::Connect::IDN", true) == true)
+ Hints.ai_flags |= AI_IDN;
+#endif
+ // see getaddrinfo(3): only return address if system has such a address configured
+ // useful if system is ipv4 only, to not get ipv6, but that fails if the system has
+ // no address configured: e.g. offline and trying to connect to localhost.
+ if (_config->FindB("Acquire::Connect::AddrConfig", true) == true)
+ Hints.ai_flags |= AI_ADDRCONFIG;
+ Hints.ai_protocol = 0;
+
+ if(_config->FindB("Acquire::ForceIPv4", false) == true)
+ Hints.ai_family = AF_INET;
+ else if(_config->FindB("Acquire::ForceIPv6", false) == true)
+ Hints.ai_family = AF_INET6;
+ else
+ Hints.ai_family = AF_UNSPEC;
+
+ // if we couldn't resolve the host before, we don't try now
+ if (bad_addr.find(Host) != bad_addr.end())
+ {
+ _error->Error(_("Could not resolve '%s'"), Host.c_str());
+ return ResultState::TRANSIENT_ERROR;
+ }
+
+ // Resolve both the host and service simultaneously
+ while (1)
+ {
+ int Res;
+ if ((Res = getaddrinfo(Host.c_str(), ServiceNameOrPort.c_str(), &Hints, &LastHostAddr)) != 0 ||
+ LastHostAddr == 0)
+ {
+ if (Res == EAI_NONAME || Res == EAI_SERVICE)
+ {
+ if (DefPort != 0)
+ {
+ ServiceNameOrPort = std::to_string(DefPort);
+ DefPort = 0;
+ continue;
+ }
+ bad_addr.insert(bad_addr.begin(), Host);
+ Owner->SetFailReason("ResolveFailure");
+ _error->Error(_("Could not resolve '%s'"), Host.c_str());
+ return ResultState::TRANSIENT_ERROR;
+ }
+
+ if (Res == EAI_AGAIN)
+ {
+ Owner->SetFailReason("TmpResolveFailure");
+ _error->Error(_("Temporary failure resolving '%s'"),
+ Host.c_str());
+ return ResultState::TRANSIENT_ERROR;
+ }
+ if (Res == EAI_SYSTEM)
+ _error->Errno("getaddrinfo", _("System error resolving '%s:%s'"),
+ Host.c_str(), ServiceNameOrPort.c_str());
+ else
+ _error->Error(_("Something wicked happened resolving '%s:%s' (%i - %s)"),
+ Host.c_str(), ServiceNameOrPort.c_str(), Res, gai_strerror(Res));
+ return ResultState::TRANSIENT_ERROR;
+ }
+ break;
+ }
+
+ LastHost = Host;
+ LastService = ServiceNameOrPort;
+ }
+
+ // When we have an IP rotation stay with the last IP.
+ auto Addresses = OrderAddresses(LastUsed != nullptr ? LastUsed : LastHostAddr);
+ std::list<Connection> Conns;
+ ResultState Result = ResultState::SUCCESSFUL;
+
+ for (auto Addr : Addresses)
+ {
+ Connection Conn(Addr, Host, Owner);
+ if (Conn.DoConnect() != ResultState::SUCCESSFUL)
+ continue;
+
+ Conns.push_back(std::move(Conn));
+
+ Result = WaitAndCheckErrors(Conns, Fd, Owner->ConfigFindI("ConnectionAttemptDelayMsec", 250), false);
+
+ if (Result == ResultState::SUCCESSFUL)
+ return ResultState::SUCCESSFUL;
+ }
+
+ if (!Conns.empty())
+ return WaitAndCheckErrors(Conns, Fd, TimeOut * 1000, true);
+ if (Result != ResultState::SUCCESSFUL)
+ return Result;
+ if (_error->PendingError() == true)
+ return ResultState::FATAL_ERROR;
+ _error->Error(_("Unable to connect to %s:%s:"), Host.c_str(), ServiceNameOrPort.c_str());
+ return ResultState::TRANSIENT_ERROR;
+}
+ /*}}}*/
+// Connect - Connect to a server /*{{{*/
+// ---------------------------------------------------------------------
+/* Performs a connection to the server (including SRV record lookup) */
+ResultState Connect(std::string Host, int Port, const char *Service,
+ int DefPort, std::unique_ptr<MethodFd> &Fd,
+ unsigned long TimeOut, aptMethod *Owner)
+{
+ if (_error->PendingError() == true)
+ return ResultState::FATAL_ERROR;
+
+ if (ConnectionAllowed(Service, Host) == false)
+ return ResultState::FATAL_ERROR;
+
+ // Used by getaddrinfo(); prefer port if given, else fallback to service
+ std::string ServiceNameOrPort = Port != 0 ? std::to_string(Port) : Service;
+
+ if(LastHost != Host || LastService != ServiceNameOrPort)
+ {
+ SrvRecords.clear();
+ if (_config->FindB("Acquire::EnableSrvRecords", true) == true)
+ {
+ GetSrvRecords(Host, DefPort, SrvRecords);
+ // RFC2782 defines that a lonely '.' target is an abort reason
+ if (SrvRecords.size() == 1 && SrvRecords[0].target.empty())
+ {
+ _error->Error("SRV records for %s indicate that "
+ "%s service is not available at this domain",
+ Host.c_str(), Service);
+ return ResultState::FATAL_ERROR;
+ }
+ }
+ }
+
+ size_t stackSize = 0;
+ // try to connect in the priority order of the srv records
+ std::string initialHost{std::move(Host)};
+ auto const initialPort = Port;
+ while(SrvRecords.empty() == false)
+ {
+ _error->PushToStack();
+ ++stackSize;
+ // PopFromSrvRecs will also remove the server
+ auto Srv = PopFromSrvRecs(SrvRecords);
+ Host = Srv.target;
+ Port = Srv.port;
+ auto const ret = ConnectToHostname(Host, Port, Service, DefPort, Fd, TimeOut, Owner);
+ if (ret == ResultState::SUCCESSFUL)
+ {
+ while(stackSize--)
+ _error->RevertToStack();
+ return ret;
+ }
+ }
+ Host = std::move(initialHost);
+ Port = initialPort;
+
+ // we have no (good) SrvRecords for this host, connect right away
+ _error->PushToStack();
+ ++stackSize;
+ auto const ret = ConnectToHostname(Host, Port, Service, DefPort, Fd,
+ TimeOut, Owner);
+ while(stackSize--)
+ if (ret == ResultState::SUCCESSFUL)
+ _error->RevertToStack();
+ else
+ _error->MergeWithStack();
+ return ret;
+}
+ /*}}}*/
+// UnwrapSocks - Handle SOCKS setup /*{{{*/
+// ---------------------------------------------------------------------
+/* This does socks magic */
+static bool TalkToSocksProxy(int const ServerFd, std::string const &Proxy,
+ char const *const type, bool const ReadWrite, uint8_t *const ToFrom,
+ unsigned int const Size, unsigned int const Timeout)
+{
+ if (WaitFd(ServerFd, ReadWrite, Timeout) == false)
+ {
+ if (ReadWrite)
+ return _error->Error("Timed out while waiting to write '%s' to proxy %s", type, URI::SiteOnly(Proxy).c_str());
+ else
+ return _error->Error("Timed out while waiting to read '%s' from proxy %s", type, URI::SiteOnly(Proxy).c_str());
+ }
+ if (ReadWrite == false)
+ {
+ if (FileFd::Read(ServerFd, ToFrom, Size) == false)
+ return _error->Error("Reading the %s from SOCKS proxy %s failed", type, URI::SiteOnly(Proxy).c_str());
+ }
+ else
+ {
+ if (FileFd::Write(ServerFd, ToFrom, Size) == false)
+ return _error->Error("Writing the %s to SOCKS proxy %s failed", type, URI::SiteOnly(Proxy).c_str());
+ }
+ return true;
+}
+
+ResultState UnwrapSocks(std::string Host, int Port, URI Proxy, std::unique_ptr<MethodFd> &Fd,
+ unsigned long Timeout, aptMethod *Owner)
+{
+ /* We implement a very basic SOCKS5 client here complying mostly to RFC1928 expect
+ * for not offering GSSAPI auth which is a must (we only do no or user/pass auth).
+ * We also expect the SOCKS5 server to do hostname lookup (aka socks5h) */
+ std::string const ProxyInfo = URI::SiteOnly(Proxy);
+ Owner->Status(_("Connecting to %s (%s)"), "SOCKS5h proxy", ProxyInfo.c_str());
+#define APT_WriteOrFail(TYPE, DATA, LENGTH) \
+ if (TalkToSocksProxy(Fd->Fd(), ProxyInfo, TYPE, true, DATA, LENGTH, Timeout) == false) \
+ return ResultState::TRANSIENT_ERROR
+#define APT_ReadOrFail(TYPE, DATA, LENGTH) \
+ if (TalkToSocksProxy(Fd->Fd(), ProxyInfo, TYPE, false, DATA, LENGTH, Timeout) == false) \
+ return ResultState::TRANSIENT_ERROR
+ if (Host.length() > 255)
+ {
+ _error->Error("Can't use SOCKS5h as hostname %s is too long!", Host.c_str());
+ return ResultState::FATAL_ERROR;
+ }
+ if (Proxy.User.length() > 255 || Proxy.Password.length() > 255)
+ {
+ _error->Error("Can't use user&pass auth as they are too long (%lu and %lu) for the SOCKS5!", Proxy.User.length(), Proxy.Password.length());
+ return ResultState::FATAL_ERROR;
+ }
+ if (Proxy.User.empty())
+ {
+ uint8_t greeting[] = {0x05, 0x01, 0x00};
+ APT_WriteOrFail("greet-1", greeting, sizeof(greeting));
+ }
+ else
+ {
+ uint8_t greeting[] = {0x05, 0x02, 0x00, 0x02};
+ APT_WriteOrFail("greet-2", greeting, sizeof(greeting));
+ }
+ uint8_t greeting[2];
+ APT_ReadOrFail("greet back", greeting, sizeof(greeting));
+ if (greeting[0] != 0x05)
+ {
+ _error->Error("SOCKS proxy %s greets back with wrong version: %d", ProxyInfo.c_str(), greeting[0]);
+ return ResultState::FATAL_ERROR;
+ }
+ if (greeting[1] == 0x00)
+ ; // no auth has no method-dependent sub-negotiations
+ else if (greeting[1] == 0x02)
+ {
+ if (Proxy.User.empty())
+ {
+ _error->Error("SOCKS proxy %s negotiated user&pass auth, but we had not offered it!", ProxyInfo.c_str());
+ return ResultState::FATAL_ERROR;
+ }
+ // user&pass auth sub-negotiations are defined by RFC1929
+ std::vector<uint8_t> auth = {{0x01, static_cast<uint8_t>(Proxy.User.length())}};
+ std::copy(Proxy.User.begin(), Proxy.User.end(), std::back_inserter(auth));
+ auth.push_back(static_cast<uint8_t>(Proxy.Password.length()));
+ std::copy(Proxy.Password.begin(), Proxy.Password.end(), std::back_inserter(auth));
+ APT_WriteOrFail("user&pass auth", auth.data(), auth.size());
+ uint8_t authstatus[2];
+ APT_ReadOrFail("auth report", authstatus, sizeof(authstatus));
+ if (authstatus[0] != 0x01)
+ {
+ _error->Error("SOCKS proxy %s auth status response with wrong version: %d", ProxyInfo.c_str(), authstatus[0]);
+ return ResultState::FATAL_ERROR;
+ }
+ if (authstatus[1] != 0x00)
+ {
+ _error->Error("SOCKS proxy %s reported authorization failure: username or password incorrect? (%d)", ProxyInfo.c_str(), authstatus[1]);
+ return ResultState::FATAL_ERROR;
+ }
+ }
+ else
+ {
+ _error->Error("SOCKS proxy %s greets back having not found a common authorization method: %d", ProxyInfo.c_str(), greeting[1]);
+ return ResultState::FATAL_ERROR;
+ }
+ union {
+ uint16_t *i;
+ uint8_t *b;
+ } portu;
+ uint16_t port = htons(static_cast<uint16_t>(Port));
+ portu.i = &port;
+ std::vector<uint8_t> request = {{0x05, 0x01, 0x00, 0x03, static_cast<uint8_t>(Host.length())}};
+ std::copy(Host.begin(), Host.end(), std::back_inserter(request));
+ request.push_back(portu.b[0]);
+ request.push_back(portu.b[1]);
+ APT_WriteOrFail("request", request.data(), request.size());
+ uint8_t response[4];
+ APT_ReadOrFail("first part of response", response, sizeof(response));
+ if (response[0] != 0x05)
+ {
+ _error->Error("SOCKS proxy %s response with wrong version: %d", ProxyInfo.c_str(), response[0]);
+ return ResultState::FATAL_ERROR;
+ }
+ if (response[2] != 0x00)
+ {
+ _error->Error("SOCKS proxy %s has unexpected non-zero reserved field value: %d", ProxyInfo.c_str(), response[2]);
+ return ResultState::FATAL_ERROR;
+ }
+ std::string bindaddr;
+ if (response[3] == 0x01) // IPv4 address
+ {
+ uint8_t ip4port[6];
+ APT_ReadOrFail("IPv4+Port of response", ip4port, sizeof(ip4port));
+ portu.b[0] = ip4port[4];
+ portu.b[1] = ip4port[5];
+ port = ntohs(*portu.i);
+ strprintf(bindaddr, "%d.%d.%d.%d:%d", ip4port[0], ip4port[1], ip4port[2], ip4port[3], port);
+ }
+ else if (response[3] == 0x03) // hostname
+ {
+ uint8_t namelength;
+ APT_ReadOrFail("hostname length of response", &namelength, 1);
+ uint8_t hostname[namelength + 2];
+ APT_ReadOrFail("hostname of response", hostname, sizeof(hostname));
+ portu.b[0] = hostname[namelength];
+ portu.b[1] = hostname[namelength + 1];
+ port = ntohs(*portu.i);
+ hostname[namelength] = '\0';
+ strprintf(bindaddr, "%s:%d", hostname, port);
+ }
+ else if (response[3] == 0x04) // IPv6 address
+ {
+ uint8_t ip6port[18];
+ APT_ReadOrFail("IPv6+port of response", ip6port, sizeof(ip6port));
+ portu.b[0] = ip6port[16];
+ portu.b[1] = ip6port[17];
+ port = ntohs(*portu.i);
+ strprintf(bindaddr, "[%02X%02X:%02X%02X:%02X%02X:%02X%02X:%02X%02X:%02X%02X:%02X%02X:%02X%02X]:%d",
+ ip6port[0], ip6port[1], ip6port[2], ip6port[3], ip6port[4], ip6port[5], ip6port[6], ip6port[7],
+ ip6port[8], ip6port[9], ip6port[10], ip6port[11], ip6port[12], ip6port[13], ip6port[14], ip6port[15],
+ port);
+ }
+ else
+ {
+ _error->Error("SOCKS proxy %s destination address is of unknown type: %d",
+ ProxyInfo.c_str(), response[3]);
+ return ResultState::FATAL_ERROR;
+ }
+ if (response[1] != 0x00)
+ {
+ char const *errstr = nullptr;
+ auto errcode = response[1];
+ bool Transient = false;
+ // Tor error reporting can be a bit arcane, lets try to detect & fix it up
+ if (bindaddr == "0.0.0.0:0")
+ {
+ auto const lastdot = Host.rfind('.');
+ if (lastdot == std::string::npos || Host.substr(lastdot) != ".onion")
+ ;
+ else if (errcode == 0x01)
+ {
+ auto const prevdot = Host.rfind('.', lastdot - 1);
+ if (prevdot == std::string::npos && (lastdot == 16 || lastdot == 56))
+ ; // valid .onion address
+ else if (prevdot != std::string::npos && ((lastdot - prevdot) == 17 || (lastdot - prevdot) == 57))
+ ; // valid .onion address with subdomain(s)
+ else
+ {
+ errstr = "Invalid hostname: onion service name must be either 16 or 56 characters long";
+ Owner->SetFailReason("SOCKS");
+ }
+ }
+ // in all likelihood the service is either down or the address has
+ // a typo and so "Host unreachable" is the better understood error
+ // compared to the technically correct "TLL expired".
+ else if (errcode == 0x06)
+ errcode = 0x04;
+ }
+ if (errstr == nullptr)
+ {
+ switch (errcode)
+ {
+ case 0x01:
+ errstr = "general SOCKS server failure";
+ Owner->SetFailReason("SOCKS");
+ break;
+ case 0x02:
+ errstr = "connection not allowed by ruleset";
+ Owner->SetFailReason("SOCKS");
+ break;
+ case 0x03:
+ errstr = "Network unreachable";
+ Owner->SetFailReason("ConnectionTimedOut");
+ Transient = true;
+ break;
+ case 0x04:
+ errstr = "Host unreachable";
+ Owner->SetFailReason("ConnectionTimedOut");
+ Transient = true;
+ break;
+ case 0x05:
+ errstr = "Connection refused";
+ Owner->SetFailReason("ConnectionRefused");
+ Transient = true;
+ break;
+ case 0x06:
+ errstr = "TTL expired";
+ Owner->SetFailReason("Timeout");
+ Transient = true;
+ break;
+ case 0x07:
+ errstr = "Command not supported";
+ Owner->SetFailReason("SOCKS");
+ break;
+ case 0x08:
+ errstr = "Address type not supported";
+ Owner->SetFailReason("SOCKS");
+ break;
+ default:
+ errstr = "Unknown error";
+ Owner->SetFailReason("SOCKS");
+ break;
+ }
+ }
+ _error->Error("SOCKS proxy %s could not connect to %s (%s) due to: %s (%d)",
+ ProxyInfo.c_str(), Host.c_str(), bindaddr.c_str(), errstr, response[1]);
+ return Transient ? ResultState::TRANSIENT_ERROR : ResultState::FATAL_ERROR;
+ }
+ else if (Owner->DebugEnabled())
+ ioprintf(std::clog, "http: SOCKS proxy %s connection established to %s (%s)\n",
+ ProxyInfo.c_str(), Host.c_str(), bindaddr.c_str());
+
+ if (WaitFd(Fd->Fd(), true, Timeout) == false)
+ {
+ _error->Error("SOCKS proxy %s reported connection to %s (%s), but timed out",
+ ProxyInfo.c_str(), Host.c_str(), bindaddr.c_str());
+ return ResultState::TRANSIENT_ERROR;
+ }
+#undef APT_ReadOrFail
+#undef APT_WriteOrFail
+
+ return ResultState::SUCCESSFUL;
+}
+ /*}}}*/
+// UnwrapTLS - Handle TLS connections /*{{{*/
+// ---------------------------------------------------------------------
+/* Performs a TLS handshake on the socket */
+struct TlsFd : public MethodFd
+{
+ std::unique_ptr<MethodFd> UnderlyingFd;
+ gnutls_session_t session;
+ gnutls_certificate_credentials_t credentials;
+ std::string hostname;
+ unsigned long Timeout;
+
+ int Fd() APT_OVERRIDE { return UnderlyingFd->Fd(); }
+
+ ssize_t Read(void *buf, size_t count) APT_OVERRIDE
+ {
+ return HandleError(gnutls_record_recv(session, buf, count));
+ }
+ ssize_t Write(void *buf, size_t count) APT_OVERRIDE
+ {
+ return HandleError(gnutls_record_send(session, buf, count));
+ }
+
+ ssize_t DoTLSHandshake()
+ {
+ int err;
+ // Do the handshake. Our socket is non-blocking, so we need to call WaitFd()
+ // accordingly.
+ do
+ {
+ err = gnutls_handshake(session);
+ if ((err == GNUTLS_E_INTERRUPTED || err == GNUTLS_E_AGAIN) &&
+ WaitFd(this->Fd(), gnutls_record_get_direction(session) == 1, Timeout) == false)
+ {
+ _error->Errno("select", "Could not wait for server fd");
+ return err;
+ }
+ } while (err < 0 && gnutls_error_is_fatal(err) == 0);
+
+ if (err < 0)
+ {
+ // Print reason why validation failed.
+ if (err == GNUTLS_E_CERTIFICATE_VERIFICATION_ERROR)
+ {
+ gnutls_datum_t txt;
+ auto type = gnutls_certificate_type_get(session);
+ auto status = gnutls_session_get_verify_cert_status(session);
+ if (gnutls_certificate_verification_status_print(status, type, &txt, 0) == 0)
+ {
+ _error->Error("Certificate verification failed: %s", txt.data);
+ }
+ gnutls_free(txt.data);
+ }
+ _error->Error("Could not handshake: %s", gnutls_strerror(err));
+ }
+ return err;
+ }
+
+ template <typename T>
+ T HandleError(T err)
+ {
+ // Server may request re-handshake if client certificates need to be provided
+ // based on resource requested
+ if (err == GNUTLS_E_REHANDSHAKE)
+ {
+ int rc = DoTLSHandshake();
+ // Only reset err if DoTLSHandshake() fails.
+ // Otherwise, we want to follow the original error path and set errno to EAGAIN
+ // so that the request is retried.
+ if (rc < 0)
+ err = rc;
+ }
+
+ if (err < 0 && gnutls_error_is_fatal(err))
+ errno = EIO;
+ else if (err < 0)
+ errno = EAGAIN;
+ else
+ errno = 0;
+ return err;
+ }
+
+ int Close() APT_OVERRIDE
+ {
+ auto err = HandleError(gnutls_bye(session, GNUTLS_SHUT_RDWR));
+ auto lower = UnderlyingFd->Close();
+ return err < 0 ? HandleError(err) : lower;
+ }
+
+ bool HasPending() APT_OVERRIDE
+ {
+ return gnutls_record_check_pending(session) > 0;
+ }
+};
+
+ResultState UnwrapTLS(std::string const &Host, std::unique_ptr<MethodFd> &Fd,
+ unsigned long const Timeout, aptMethod * const Owner,
+ aptConfigWrapperForMethods const * const OwnerConf)
+{
+ if (_config->FindB("Acquire::AllowTLS", true) == false)
+ {
+ _error->Error("TLS support has been disabled: Acquire::AllowTLS is false.");
+ return ResultState::FATAL_ERROR;
+ }
+
+ int err;
+ TlsFd *tlsFd = new TlsFd();
+
+ tlsFd->hostname = Host;
+ tlsFd->UnderlyingFd = MethodFd::FromFd(-1); // For now
+ tlsFd->Timeout = Timeout;
+
+ if ((err = gnutls_init(&tlsFd->session, GNUTLS_CLIENT | GNUTLS_NONBLOCK)) < 0)
+ {
+ _error->Error("Internal error: could not allocate credentials: %s", gnutls_strerror(err));
+ return ResultState::FATAL_ERROR;
+ }
+
+ FdFd *fdfd = dynamic_cast<FdFd *>(Fd.get());
+ if (fdfd != nullptr)
+ {
+ gnutls_transport_set_int(tlsFd->session, fdfd->fd);
+ }
+ else
+ {
+ gnutls_transport_set_ptr(tlsFd->session, Fd.get());
+ gnutls_transport_set_pull_function(tlsFd->session,
+ [](gnutls_transport_ptr_t p, void *buf, size_t size) -> ssize_t {
+ return reinterpret_cast<MethodFd *>(p)->Read(buf, size);
+ });
+ gnutls_transport_set_push_function(tlsFd->session,
+ [](gnutls_transport_ptr_t p, const void *buf, size_t size) -> ssize_t {
+ return reinterpret_cast<MethodFd *>(p)->Write((void *)buf, size);
+ });
+ }
+
+ if ((err = gnutls_certificate_allocate_credentials(&tlsFd->credentials)) < 0)
+ {
+ _error->Error("Internal error: could not allocate credentials: %s", gnutls_strerror(err));
+ return ResultState::FATAL_ERROR;
+ }
+
+ // Credential setup
+ std::string fileinfo = OwnerConf->ConfigFind("CaInfo", "");
+ if (fileinfo.empty())
+ {
+ // No CaInfo specified, use system trust store.
+ err = gnutls_certificate_set_x509_system_trust(tlsFd->credentials);
+ if (err == 0)
+ Owner->Warning("No system certificates available. Try installing ca-certificates.");
+ else if (err < 0)
+ {
+ _error->Error("Could not load system TLS certificates: %s", gnutls_strerror(err));
+ return ResultState::FATAL_ERROR;
+ }
+ }
+ else
+ {
+ // CA location has been set, use the specified one instead
+ gnutls_certificate_set_verify_flags(tlsFd->credentials, GNUTLS_VERIFY_ALLOW_X509_V1_CA_CRT);
+ err = gnutls_certificate_set_x509_trust_file(tlsFd->credentials, fileinfo.c_str(), GNUTLS_X509_FMT_PEM);
+ if (err < 0)
+ {
+ _error->Error("Could not load certificates from %s (CaInfo option): %s", fileinfo.c_str(), gnutls_strerror(err));
+ return ResultState::FATAL_ERROR;
+ }
+ }
+
+ if (not OwnerConf->ConfigFind("IssuerCert", "").empty())
+ {
+ _error->Error("The option '%s' is not supported anymore", "IssuerCert");
+ return ResultState::FATAL_ERROR;
+ }
+ if (not OwnerConf->ConfigFind("SslForceVersion", "").empty())
+ {
+ _error->Error("The option '%s' is not supported anymore", "SslForceVersion");
+ return ResultState::FATAL_ERROR;
+ }
+
+ // For client authentication, certificate file ...
+ std::string const cert = OwnerConf->ConfigFind("SslCert", "");
+ std::string const key = OwnerConf->ConfigFind("SslKey", "");
+ if (cert.empty() == false)
+ {
+ if ((err = gnutls_certificate_set_x509_key_file(
+ tlsFd->credentials,
+ cert.c_str(),
+ key.empty() ? cert.c_str() : key.c_str(),
+ GNUTLS_X509_FMT_PEM)) < 0)
+ {
+ _error->Error("Could not load client certificate (%s, SslCert option) or key (%s, SslKey option): %s", cert.c_str(), key.c_str(), gnutls_strerror(err));
+ return ResultState::FATAL_ERROR;
+ }
+ }
+
+ // CRL file
+ std::string const crlfile = OwnerConf->ConfigFind("CrlFile", "");
+ if (crlfile.empty() == false)
+ {
+ if ((err = gnutls_certificate_set_x509_crl_file(tlsFd->credentials,
+ crlfile.c_str(),
+ GNUTLS_X509_FMT_PEM)) < 0)
+ {
+ _error->Error("Could not load custom certificate revocation list %s (CrlFile option): %s", crlfile.c_str(), gnutls_strerror(err));
+ return ResultState::FATAL_ERROR;
+ }
+ }
+
+ if ((err = gnutls_credentials_set(tlsFd->session, GNUTLS_CRD_CERTIFICATE, tlsFd->credentials)) < 0)
+ {
+ _error->Error("Internal error: Could not add certificates to session: %s", gnutls_strerror(err));
+ return ResultState::FATAL_ERROR;
+ }
+
+ if ((err = gnutls_set_default_priority(tlsFd->session)) < 0)
+ {
+ _error->Error("Internal error: Could not set algorithm preferences: %s", gnutls_strerror(err));
+ return ResultState::FATAL_ERROR;
+ }
+
+ if (OwnerConf->ConfigFindB("Verify-Peer", true))
+ {
+ gnutls_session_set_verify_cert(tlsFd->session, OwnerConf->ConfigFindB("Verify-Host", true) ? tlsFd->hostname.c_str() : nullptr, 0);
+ }
+
+ // set SNI only if the hostname is really a name and not an address
+ {
+ struct in_addr addr4;
+ struct in6_addr addr6;
+
+ if (inet_pton(AF_INET, tlsFd->hostname.c_str(), &addr4) == 1 ||
+ inet_pton(AF_INET6, tlsFd->hostname.c_str(), &addr6) == 1)
+ /* not a host name */;
+ else if ((err = gnutls_server_name_set(tlsFd->session, GNUTLS_NAME_DNS, tlsFd->hostname.c_str(), tlsFd->hostname.length())) < 0)
+ {
+ _error->Error("Could not set host name %s to indicate to server: %s", tlsFd->hostname.c_str(), gnutls_strerror(err));
+ return ResultState::FATAL_ERROR;
+ }
+ }
+
+ // Set the FD now, so closing it works reliably.
+ tlsFd->UnderlyingFd = std::move(Fd);
+ Fd.reset(tlsFd);
+
+ // Do the handshake.
+ err = tlsFd->DoTLSHandshake();
+
+ if (err < 0)
+ return ResultState::TRANSIENT_ERROR;
+
+ return ResultState::SUCCESSFUL;
+}
+ /*}}}*/